Re: [gentoo-user] WPA Supplicant

[Mick]

On Sunday 24 April 2011 13:37:03 dhkuhl@×××××××××.net wrote:
> I'm trying to get wireless working reliably on my laptop.  I have followed
> the documentation, but still have a lot of questions . . . especially
> since it only seems to work sometimes.
>
> First, I'm using WPA Supplicant without the gui tools.

run wpa_gui from a terminal and a lot of what you're asking below will become 
self-explanatory.


> Second, I'm in NYC and there are a lot of networks I can use around town.
>
> Third, Is there a way I can control the services I use from the Grub menu?
> Since the laptop has a wireless card and an RJ45 jack, I'd like to be able
> boot and not use one or the other.  Since I know if I'm not physically
> connected to a network, there's really no reason to even try eth0.

Check /etc/conf.d/rc and in particular:

# RC_NET_STRICT_CHECKING allows some flexibility with the 'net' service.
# The following values are allowed:
#  none  - The 'net' service is always considered up.
#  no    - This basically means that at least one net.* service besides net.lo
#          must be up.  This can be used by notebook users that have a wifi 
and
#          a static nic, and only wants one up at any given time to have the
#          'net' service seen as up.
#  lo    - This is the same as the 'no' option, but net.lo is also counted.
#          This should be useful to people that do not care about any specific
#          interface being up at boot.
#  yes   - For this ALL network interfaces MUST be up for the 'net' service to
#          be considered up.

RC_NET_STRICT_CHECKING="no"

(or you can use "lo")


> Forth, The problem.  I'm not sure how wpa_supplicant works or how it should
> work.  The wpa_supplicant man page gives a few examples on how to run it,
> but when I look at the process list it seems to be run by another program
> called wpa_cli.  There's also a shell script in /etc/wpa/supplicant that
> looks like it can start or stop it with CONNECT or DISCONNECT. 1) Do I
> need to enter networks in wpa_supplicant.conf or does wpa_supplicant scan
> for networks and connect to whatever's available?

The latter.

You can however enter manually in /etc/wpa_supplicant/wpa_supplicant.conf 
particular parameters (keys and what not) of known networks to which you 
connect as a matter of preference.


> 2) If I have multiple
> networks available how does wpa_supplicant choose which to connect to and
> can I specify which one I want?

It'll connect to:

a) Any network you have specified in your 
/etc/wpa_supplicant/wpa_supplicant.conf according to the preference you have 
set up therein.

b) Any network it finds.

c) Any network you select with wpa_cli, or select/enable/disable in wpa_gui.


> 3) How should wpa_supplicant be started,
> stopped and restarted?  What should be used for this:  wpa_supplicant,
> wpa_cli, or wpa_cli.sh?  I don't see anything in /etc/init.d for that, but
> it looks like netmount may be doing it.

You need to define it in /etc/conf.d/net:

modules=( "wpa_supplicant" )
wpa_supplicant_wlan0="-Dwext"  

(adjust this according to the name of your wireless iface and driver).


> 4) The documentation doesn't say
> to, but the way I got wireless working is by creating a link net.wlan0 ->
> net.lo in the /etc/init.d directory.  Is this correct?

It depends which documentation you are looking at.  I am sure that this is 
explained in the gentoo Handbook and associated documentation.

This is the link you need:

lrwxrwxrwx  1 root root     6 Dec 16 14:26 net.wlan0 -> net.lo

but you should have also configured /etc/conf.d/net with your desired settings 
or just defaults will run.


> I think that's why
> it's starting automatically when I boot too, because I never added it with
> rc-update so netmount must be picking it up.


> 5) This is the most puzzling
> thing.  When wpa_supplicant starts even though I get a inet address I
> can't always get to the internet.  Why does the panel applet says I'm
> connected and ifconfig shows an inet address but firefox and ping can't
> reach a site like yahoo or google?

This could well be a dns server/repeater issue.

If you can ping the IP address of google, but not the domain name of it, then 
the problem is that you do not have access to a DNS repeater.  Look in your 
/etc/resolve.conf to see if there is a line saying:

nameserver XXX.XXX.XX.XX

if it is absent then you have not connected to a namesever.  This is a router 
issue and it could be controlled by some authentication scheme.  A lot of 
wireless services offered by coffee shops, libraries, etc. may give you an IP 
address automatically, but then require you use your browser to register with 
their authentication server (using a passwd that they provide after you pay 
them for the privilege).

Open access points with no encryption and no DNS authentication requirements 
should allow you to connect seamlessly to the Internet.


> 6) For networks where I have a
> password, should that go in wpa_supplicant.conf as plain text or should it
> be encrypted?

This can be a confusing endeavour because some routers will only accept 
certain characters in a passphrase, so you could be failing to connect due to 
the peculiarities of the router.  The passphrase should be entered as provided 
by the router owner, then a hex key generated with wpa_passphrase (look at man 
wpa_passphrase).  Then enter the hex key in your wpa_supplicant.conf, or your 
wpa_gui.

HTH for now, ask more as you need it.
-- 
Regards,
Mick